Antenna structure



Dec, 26, 1950 L. A. DE ROSA ANTENNA STRUCTURE Filed Nov. 14, 1945 IN V EN TOR. 100/6 ,4. 0E 190.5%

A T'TOFA/IF) Patented Dec. 26 1950 1' UlD STATS 2,535,049 ANTENNA srnno'rnnn Application November 14, 1945, Serial No. 628,609

4 Claims. 1

This invention relates to antennas and more particularly to antennas for use with a plurality of high frequencies.

In certain applications of the radio communications art particularly with radio location and direction finding systems, it is frequently required to vary the frequency of transmission. Since the radiation patterns obtainable from such systems are dependent on the frequency employed, it becomes necessary to adjust the antenna arrays of these systems with changes in frequency, as for instance, if a given radiation pattern is to be maintained,

It is an object of this invention to provide an adjustable antenna array.

It is a further object to provide a dipole antenna array wherein both the driven and the parasitic radiators are adjustable as to distance one from the other.

In accordance with my invention I provide a directive antenna array which comprises a supporting member and a driven and a parasitic antenna on each of the ends of the supporting member. Each of the radiating members is pivotally secured to the end of the supporting member so as to provide for a variation in the angle of the radiators in respect to the supporting member. Each of the parasitic radiators in addition is also provided with a mechanism for straight line motion with reference to its pivot.

In accordance with another feature of the invention, the parasitic and the driven radiators are simultaneously movable to vary their right angular distance from the supporting member.

These and other objects and features of the invention will become more apparent upon consideration of the following detailed description of an embodiment of the invention to be read in connection with the accompanying drawing, wherein:

Fig. 1 represents a view in elevation, partly in perspective, of an antenna array in accordance with the invention; and

Fig. 2 is a perspective view of another embodiment of my invention.

Referring now to the drawings, I provide a supporting member I which is preferably tubular and supplied with an upright supporting member 2 at each end. Since the structures at the ends of the supporting member l are identical, reference will be made in the description only to one of them. The supporting member 2 carries thereon a rotatable arm 3 which is pivoted at 4. This arm, preferably at its end adjacent the pivot, carries a scale graduated in degrees as at 5. The

arm 3 is constructed to rigidly support a radiating member or dipole antenna 8. The dipole shown here is of the folded type, but may, of course, assume other forms. On the other end of the supporting member 2 a second rotatable arm in the form of a straight-line motion linkage mechanism 1 is supported on a pivot 23. The mechanism 1 carries means 9 for supporting a parasitic radiator or antenna H] which is disposed substantially parallel to the radiator 6.

over suitable conducting means H which is dis-- posed within the tubular member l. Suitable angular scales are provided on circular terminations: I2 and it of the arms of the link mechanism '1 which are joined at the pivot 53.

When the frequency of the equipment has been. changed the spacing between the two driven antennas 8 must be correspondingly changed in or-- der to get the proper distribution of energy. At the same time, the spacing between parasitic antennas l8 and the spacing between the driven antenna 6 and its corresponding parasitic it must be changed. In order to accomplish this result, it is only necessary to swing the arms 3 toward or away from each other in an angle which is measured on the scale 5. If the desired spacing between the two driven antennas is attained as measured along the member l the arms 3 are suitably clamped or otherwise locked in place. The spacing of the two parasitics may be similarly changed by an adjustment of their angular position as read on the scales l2 and I3. In order to vary or maintain a desired spacing between the two parasitics it, the link mechanism 5 permits a straight line motion of the parasitic Ill, parallel to the member I which also causes a change in its angular position. After adjustment, all of the movable elements may be tightened in place.

In the embodiment of Fig. 2, the supporting member I is preferably mounted on an antenna mast it. The driven and parasitic radiating members l5 and E6 respectively, are structurally similar in this case and are mounted for simultaneous movement by means of a cable-pulley combination comprising an endless cable H and a pulley H? at each end of the member I. Corner pulleys l9 and 20 are provided at the junction of the antenna mast M and member 5. Both the radiators I5 and it are supported parallel to the mast It by means of link members 2! and 22, of which the link member 2! is pivotall supported at 23, i. e., at the end of the member I. The link member 22 has one end thereof pivotally sup- The driven antenna 6 is supplied with radiant energy ported on a sleeve 24 which slides over the member I and has an ear or extension 25 engaging one side of the cable II, the other side of the cable being engaged by the corresponding extension associated with the other two radiators. The other end of the link member 22 may be loosely joined for pivotal movement with respect to the unsupported end of the member 2 I. The radiator I6 is supported at the point of junction of members 2I and 22. Since the structure supporting the member I5 and the counterpart of the two radiators at the other end of the member I are identical with that described in connection with member I6, it will not be necessary to describe these in detail. The cable I! may be actuated by means of a crank mechanism 26 which is arranged to turn a pulley 21 disposed within the tubular antenna mast I4.

The operation of the antenna array shown at Fig. 2 will be self evident from the inspection of the figure. The spacing between the two radiating members I5 and I6 may be varied by simply turning the crank which will cause rotation of the pulley I8 and its counterpart on the other end of member I whereby the sliding sleeve member 24 will be pulled forward or backward, as the case may be, thus causing a variation in the distance between the two radiating members and of the distance between the corresponding driven and parasitic antenna and each end of the member I as desired, the movement of the four antennas being simultaneous.

It will thus be seen from the above that a highly flexible antenna array has been provided which makes it useful over a wide range of frequencies.

While I have described above the principles of my invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation on the scope of my invention as defined in the objects and the accompanying claims.

I claim:

1. An antenna array comprising a supporting member, two pairs of radiators, the pairs being disposed adjacent opposite ends of said supporting member, the two radiators of each pair being oppositely disposed about an end of said supporting member and parallel to one another, link means for effecting movement of each radiator in an are about its respective end of said supporting member, and means connected to all said link means for simultaneously moving said radiators towards or away from the two ends of said supporting member, whereby the distance between said radiators of each pair and between corresponding radiators of the two pairs may be varied.

2. An array according to claim '1 wherein said radiators are supported in a perpendicular direction with respect to said supporting member by means of supporting link members, one for each radiator, pivoted at the end of said supporting member, and said link means includes an actuating link member for each radiator, each actuating link being of greater length than its corresponding supporting link member, and said means for operating said link means includes a sleeve member on said supporting member for 5 each pair of radiators to which the said actuating link is attached, and a cable connected to said sleeve members for simultaneous movement of said sleeves toward and away from the ends of said supporting member.

3. An array according to claim 1 wherein said radiators are supported in a perpendicular direction with respect to said supporting member by means of supporting link members, one for each radiator pivoted at the end of said supporting member.

4. An array according to claim 3 wherein said link means include an actuating link member for each radiator, each actuating link member being greater in length than its corresponding supporting link member.

LOUIS A. DE ROSA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,663,635 Loughridge Mar. 27, 1928 2,073,085 Wells Mar. 9, 1937 2,145,024 Bruce Jan. 24, 1939 2,183,784 Carter Dec. 19, 1939 2,199,050 Jenkins Apr. 30, 1940 2,227,929 Goddard Jan. 7, 1941 2,299,218 Fener Oct. 20, 1942 2,334,856 Atkinson Nov. 23, 1943 FOREIGN PATENTS Number Country Date 440,506 Germany Feb. 11, 1927 136,743 Austria Mar. '10, 1934 OTHER REFERENCES Radio News, November 1937, article by L. Cookaday, pages 266, 267, and 317. 

